Fuel tank baffle with pivotable vanes

ABSTRACT

Methods and systems are provided for regulating fuel flow in a fuel tank. In one example, a method may comprise fueling a fuel tank by receiving a nozzle into a filler tube which extends into a fuel tank to fuel the fuel tank, and directing fuel through the tube against vanes in a baffle which forms a compartment within the tank. Additionally, the method may comprise enabling the vanes to open so that pressure within the compartment remains below a level which would otherwise cause shut off the nozzle during the fueling.

FIELD

The present description relates generally to a vehicle fuel system.

BACKGROUND/SUMMARY

Fuel tanks may be utilized in vehicle systems for storing fuel to beused during combustion in an engine of the vehicle system. Duringvehicle operation, fuel may be displaced within the fuel tank due tochanges in velocity of the vehicle, such as during cornering, braking,and acceleration. When displaced, fuel may impact walls of the tank andgenerate noise. Noise produced by these impacts may be more apparentwith hybrid vehicles, since they may operate with minimal interior noisewhen fuel combustion is deactivated. As such, liquid fuel tanks forautomotive vehicles are designed with various constructions to reducenoise, vibration and ride harshness generated by the motion of fuelwithin the fuel tank.

For example, U.S. Pat. No. 5,850,933 discloses a fuel tank including oneor more baffles, which extend between opposite ends of the tank so as torestrict fuel flow within the tank. As such, the impact force andtherefore the noise produced from fuel hitting the walls of the fueltank may be reduced. Further, many fuel tanks comprise bafflesconstructed with holes, so that fuel may still flow through the baffle,but in a restricted manner. In this way, the velocity of fuel withrespect to the fuel tank may be attenuated while maintaining the overallstorage volume of the tank.

However, the inventors herein have recognized potential issues with suchfuel tank systems. As an example, during refueling, the baffles mayrestrict the flow of fuel into the fuel tank. Specifically, fuelentering the fuel tank may bounce off the baffle wall and spray backtowards the refueling nozzle. Thus, the baffle wall may act as a flowrestriction for fuel entering the tank during refueling. Fuel enteringthe tank may therefore be impeded and/or confined by the baffle wall.This may result in elevated pressures and/or liquid levels on therefueling side of the baffle as compared to regions of the fuel tank onthe opposite side of the baffle. As such, the fuel pump may be shut offbefore the fuel tank is filled. In another example, vapor pressure inthe fuel tank may increase due to the fuel bouncing off the baffle wall.Increases in the fuel tank pressure may result in corresponding rises inloading of a fuel vapor storage canister of the fuel tank system.

In one example, the issues described above may be at least partlyaddressed by a method for receiving a nozzle into a filler tube whichmay extend into a fuel tank to fuel the fuel tank, and directing fuelthrough said tube against vanes in a baffle which may form a compartmentwithin said tank and during said fueling, enabling said vanes to open sothat pressure within said compartment may remain below a level which mayotherwise cause shut off said nozzle.

In some examples, enabling said vanes to open may comprise a mechanicalrelease of said vanes in response to insertion of said nozzle. However,in other examples, enabling of said vanes to open may comprise anelectro-mechanical release of said vanes by a relay in response toinsertion of said nozzle. In still further examples enabling said vanesto open may comprise pressure exerted by said fuel acting against saidvanes during said fueling which may be sufficient to overcome a weightof said vanes which may be exerting a closing force on said vanes.

In another representation, the issues described above may be at leastpartly addressed by a method comprising fueling a fuel tank by receivinga nozzle into a filler tube which may extend into said tank anddirecting fuel through said tube against vanes in a baffle which mayform a compartment within said tank, where said vanes may include aplurality of holes to allow a portion of said fuel to flow therethrough.During said fueling, the method may additionally or alternativelycomprise enabling said vanes to open so that pressure within saidcompartment may remain below a level which would otherwise cause shutoff said nozzle.

In further examples, the method may comprise routing fuel vapors fromsaid tank into a fuel vapor recovery system. In another example, themethod may comprise supplying said fuel from said tank to an internalcombustion engine. In yet other examples, the method may additionally oralternatively comprise periodically purging at least a portion of saidfuel vapors from said tank and said fuel vapor recovery system into saidengine. In some examples, internal combustion may drive a motor vehicleand said baffle may reduce sloshing of said fuel and generation of saidfuel vapors while said motor vehicle is being driven.

In this way, fuel tank noise may be reduced, while the storage capacityof the fuel tank may be increased. By including baffles with adjustablevanes, the fuel tank may still offer the same sound reduction benefitsof conventional fuel tank systems, while also reducing prematurerefueling shutoffs and fuel vapor canister loading. During refueling,the vanes may be adjusted to a first position so that fuel may flow tothe extremities of the tank, relatively unrestricted. In this way, theamount of fuel impacting the baffle during refueling may be reduced. Asa result, vapor pressure in the fuel tank, and canister loading may bereduced. However, after refueling, the baffles may be adjusted to aclosed second position, so that movement of fuel within the fuel tankmay be restricted and therefore noise produced from the fuel sloshingaround in the fuel tank may be reduced.

It should be understood that the summary above is provided to introducein simplified form a selection of concepts that are further described inthe detailed description. It is not meant to identify key or essentialfeatures of the claimed subject matter, the scope of which is defineduniquely by the claims that follow the detailed description.Furthermore, the claimed subject matter is not limited toimplementations that solve any disadvantages noted above or in any partof this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic diagram of an example vehicle system.

FIG. 2 shows a schematic diagram of an example engine system which maybe included in the vehicle system of FIG. 1.

FIG. 3 illustrates an exterior side perspective view of an embodiment ofa fuel tank which may be included in the vehicle system of FIG. 1 and/orengine system of FIG. 2.

FIG. 4 illustrates an interior side perspective view of the fuel tank ofFIG. 3.

FIG. 5A illustrates a side perspective view of a baffle comprising whichmay be included in the fuel tank of FIGS. 3-4 comprising one or morevanes in an open first position.

FIG. 5B illustrates a side perspective view of a baffle which may beincluded in the fuel tank of FIGS. 3-4 comprising one or more vanes in aclosed second position.

FIG. 6A illustrates a cross-sectional view of the baffle shown in FIG.5A with the vanes in the open first position.

FIG. 6B illustrates a cross-sectional view of the baffle shown in FIG.5B with the vanes in the closed second position.

FIG. 7 shows a flow chart of a method for regulating a flow of fuel intoand out of a fuel tank.

FIG. 8 shows a flow chart of a method for adjusting a position of one ormore vanes of a baffle within a fuel tank based on engine operatingconditions.

DETAILED DESCRIPTION

The following description relates to systems and methods for regulatingfuel flow within a fuel tank. A vehicle system, such as the vehiclesystem shown in FIG. 1, may comprise an engine for propelling thevehicle system. In some examples, the vehicle system may be a hybridelectric vehicle (HEV) and may also include a battery and/or motor forpropelling the vehicle system. Thus, either the battery or the engine,or both, may provide power to the vehicle system. An example enginesystem that may be included in the vehicle system is shown in FIG. 2.Liquid fuel used for combustion by the engine, may be stored in a fueltank (FIGS. 1-2). Example fuel tanks are shown in FIGS. 3-4.

The fuel tanks may comprise one or more baffles for restricting the flowof fuel within the tank. As shown in the example baffles of FIGS. 5A-5B,the baffles may comprise one or more adjustable vanes, which may beadjusted between an open first position and a closed second position.Example open and closed vane positions are shown in FIGS. 6A-6B. Asdescribed in the example method in FIGS. 7-8, the position of the vanes,and therefore the flow of fuel within the fuel tank, may be adjustedbased on vehicle and/or engine operating conditions. Specifically, thevanes may be adjusted to the open first position during refueling, andotherwise may be adjusted to the closed second position. In this way,the vane-containing baffle may restrict fuel flow within the fuel tankwhile the vehicle system is being driven, thus mitigating noise producedby the fuel tank. However, pressure in the fuel tank may be reducedduring refueling by adjusting the vanes to the open first position,thereby allowing relatively unrestricted flow of fuel in the fuel tank.

FIG. 1 illustrates an example vehicle system 100 as shown from a topview. Vehicle system 100 includes a vehicle body 1 with a front end,labeled “FRONT”, and a back end labeled “BACK.” Vehicle system 100 mayinclude a plurality of wheels 30. For example, as shown in FIG. 1,vehicle system 100 may include a first pair of wheels adjacent to thefront end of the vehicle and a second pair of wheels adjacent the backend of the vehicle. Forward motion of the vehicle should be understoodto mean motion of the vehicle toward the front end of the vehicle andbackward motion of the vehicle should be understood to mean motion ofthe vehicle toward the back end of the vehicle.

Vehicle system 100 includes a fuel burning engine 110 and a motor 20. Asa non-limiting example, engine 110 comprises an internal combustionengine and motor 20 comprises an electric motor. Motor 20 may beconfigured to utilize or consume a different energy source than engine110. For example, engine 110 may consume a liquid fuel (e.g., gasoline)to produce an engine output while motor 20 may consume electrical energyto produce a motor output. As such, a vehicle system 100 may be referredto as a hybrid electric vehicle (HEV).

Vehicle system 100 may utilize a variety of different operational modesdepending on operating conditions encountered by the vehicle propulsionsystem. Some of these modes may enable engine 110 to be maintained in anoff state (i.e. set to a deactivated state) where combustion of fuel atthe engine is discontinued. For example, under select operatingconditions, motor 20 may propel the vehicle via drive wheel 30 asindicated by line 22 while engine 110 is deactivated.

During other operating conditions, engine 110 may be set to adeactivated state (as described above) while motor 20 may be operated tocharge energy storage device 50. For example, motor 20 may receive wheeltorque from drive wheel 30 as indicated by line 22 where the motor mayconvert the kinetic energy of the vehicle to electrical energy forstorage at energy storage device 50 as indicated by line 24. Thisoperation may be referred to as regenerative braking of the vehicle.Thus, motor 20 can provide a generator function in some embodiments.However, in other embodiments, generator 60 may instead receive wheeltorque from drive wheel 30, where the generator may convert the kineticenergy of the vehicle to electrical energy for storage at energy storagedevice 50 as indicated by line 62.

During still other operating conditions, engine 110 may be operated bycombusting fuel received from fuel system 40 as indicated by line 42.For example, engine 110 may be operated to propel the vehicle via drivewheel 30 as indicated by line 12 while motor 20 is deactivated. Duringother operating conditions, both engine 110 and motor 20 may each beoperated to propel the vehicle via drive wheel 30 as indicated by lines12 and 22, respectively. A configuration where both the engine and themotor may selectively propel the vehicle may be referred to as aparallel type vehicle propulsion system. Note that in some embodiments,motor 20 may propel the vehicle via a first set of drive wheels andengine 110 may propel the vehicle via a second set of drive wheels.

In other embodiments, vehicle propulsion system 100 may be configured asa series type vehicle system, whereby the engine does not directlypropel the drive wheels. Rather, engine 110 may be operated to powermotor 20, which may in turn propel the vehicle via drive wheel 30 asindicated by line 22. For example, during select operating conditions,engine 110 may drive generator 60, which may in turn supply electricalenergy to one or more of motor 20 as indicated by line 14 or energystorage device 50 as indicated by line 62. As another example, engine110 may be operated to drive motor 20 which may in turn provide agenerator function to convert the engine output to electrical energy,where the electrical energy may be stored at energy storage device 50for later use by the motor. As yet another example, engine 110 may beoperated to drive generator 60, which may in turn provide a generatorfunction to convert the engine output to electrical energy, where theelectrical energy may be stored at energy storage device 50 for lateruse by the motor. The vehicle propulsion system may be configured totransition between two or more of the operating modes described abovedepending on operating conditions.

Fuel system 40 may include one or more fuel storage tanks 126 forstoring fuel on-board the vehicle. For example, fuel tank 126 may storeone or more liquid fuels, including but not limited to: gasoline,diesel, and alcohol fuels. In some examples, the fuel may be storedon-board the vehicle as a blend of two or more different fuels. Forexample, fuel tank 126 may be configured to store a blend of gasolineand ethanol (e.g., E10, E85, etc.) or a blend of gasoline and methanol(e.g., M10, M85, etc.), whereby these fuels or fuel blends may bedelivered to engine 110 as indicated by line 42. Still other suitablefuels or fuel blends may be supplied to engine 110, where they may becombusted at the engine to produce an engine output. The engine outputmay be utilized to propel the vehicle as indicated by line 12 or torecharge energy storage device 50 via motor 20 or generator 60.

In some examples, as shown in FIG. 1, fuel tank 126 may be packaged inthe vehicle adjacent to a wheel axle, e.g., adjacent to wheel axle 3towards the back side of the vehicle. However, in other examples, fueltank 126 may be positioned in another region of the vehicle, e.g.,adjacent to a front axle or other location. Further, as described inmore detail below, in some examples, fuel tank 126 may have a shelf tankdesign where a depth of a first region of the fuel tank, e.g., a rearregion of the fuel tank, is less than a depth of a second region of thetank, e.g., a front region. Further, fuel tank 126 may include aplurality of components, such as support structures and one or more fuelpumps.

For example, fuel tank 126 may be substantially composed of a plasticand may include reinforcement elements therein. However, in otherexamples, fuel tank 126 may be substantially composed of a metal and/oralloy, and may include reinforcement elements therein. In still furtherexamples, the fuel tank 126 may be composed of both plastic and metal.Further, as described in detail below with regard to FIGS. 4-5, fueltank 126 may include one or more baffles coupled to walls of the fueltank to assist in dampening waves of liquid fuel within the tank duringvehicle motion. In some embodiments, the fuel tank 126 may include abaffle positioned oblique and/or perpendicular to longitudinal wavesflowing in the tank 126. The baffle may be coupled to long and shortvertical walls of the fuel tank, and may include undulations beingwave-shaped. Further still, other shapes may be used, if desired as willbe described in greater detail below with reference to FIGS. 4-5.

In some embodiments, energy storage device 50 may be configured to storeelectrical energy that may be supplied to other electrical loadsresiding on-board the vehicle (other than the motor), including cabinheating and air conditioning, engine starting, headlights, cabin audioand video systems, etc. As a non-limiting example, energy storage device50 may include one or more batteries and/or capacitors.

Control system 90 may communicate with one or more of engine 110, motor20, fuel system 40, energy storage device 50, and generator 60. Controlsystem 90 may receive sensory feedback information from one or more ofengine 110, motor 20, fuel system 40, energy storage device 50, andgenerator 60. Further, control system 90 may send control signals to oneor more of engine 110, motor 20, fuel system 40, energy storage device50, and generator 60 responsive to this sensory feedback. Control system90 may receive an indication of an operator requested output of thevehicle propulsion system from a vehicle operator 130. For example,control system 90 may receive sensory feedback from pedal positionsensor 134 which communicates with input device 132. Input device 132may refer schematically to a brake pedal and/or an accelerator pedal.

Energy storage device 50 may periodically receive electrical energy froma power source 80 residing external to the vehicle (e.g., not part ofthe vehicle) as indicated by line 84. As a non-limiting example, vehiclesystem 100 may be configured as a plug-in hybrid electric vehicle (HEV),whereby electrical energy may be supplied to energy storage device 50from power source 80 via an electrical energy transmission cable 82.During a recharging operation of energy storage device 50 from powersource 80, electrical transmission cable 82 may electrically coupleenergy storage device 50 and power source 80. While the vehiclepropulsion system is operated to propel the vehicle, electricaltransmission cable 82 may disconnected between power source 80 andenergy storage device 50. Control system 90 may identify and/or controlthe amount of electrical energy stored at the energy storage device,which may be referred to as the state of charge (SOC).

In other embodiments, electrical transmission cable 82 may be omitted,where electrical energy may be received wirelessly at energy storagedevice 50 from power source 80. For example, energy storage device 50may receive electrical energy from power source 80 via one or more ofelectromagnetic induction, radio waves, and electromagnetic resonance.As such, it should be appreciated that any suitable approach may be usedfor recharging energy storage device 50 from a power source that doesnot comprise part of the vehicle. In this way, motor 20 may propel thevehicle by utilizing an energy source other than the fuel utilized byengine 110.

Fuel system 40 may periodically receive fuel from a fuel source residingexternal to the vehicle. As a non-limiting example, vehicle system 100may be refueled by receiving fuel via a fuel dispensing nozzle 170 asindicated by line 172. In some embodiments, fuel tank 126 may beconfigured to store the fuel received from fuel dispensing nozzle 170until it is supplied to engine 110 for combustion. In some embodiments,control system 90 may receive an indication of the level of fuel storedat fuel tank 126 via a fuel level sensor as described in greater detailbelow with reference to FIGS. 2-4. The level of fuel stored at fuel tank126 (e.g., as identified by the fuel level sensor) may be communicatedto the vehicle operator, for example, via a fuel gauge or indicationlamp indicated at 96.

Vehicle system 100 may be configured to utilize a secondary form ofenergy (e.g., electrical energy) that is periodically received from anenergy source that is not otherwise part of the vehicle.

The vehicle system 100 may also include a message center 96, ambienttemperature/humidity sensor 98, and a roll stability control sensor,such as a lateral and/or longitudinal and/or yaw rate sensor(s) 99. Themessage center may include indicator light(s) and/or a text-baseddisplay in which messages are displayed to an operator, such as amessage requesting an operator input to start the engine, as discussedbelow. The message center may also include various input portions forreceiving an operator input, such as buttons, touch screens, voiceinput/recognition, etc. In an alternative embodiment, the message centermay communicate audio messages to the operator without display.

It should be understood that though FIG. 1 shows a plug-in hybridelectric vehicle, in other examples, vehicle system 100 may be a hybridvehicle without plug-in components. Further, in other examples, vehiclesystem 100 may not be a hybrid vehicle but may be another type ofvehicle with other propulsion mechanisms, e.g., a vehicle with agasoline engine or a diesel engine which may or may not include otherpropulsion systems. Thus, in some examples, vehicle system 100 may bepowered by only by engine 110, and not by energy storage device 50and/or motor 20.

Referring now to FIG. 2, it shows aspects of an example engine system200 which may be included in an automotive vehicle such as the vehiclesystem 100 shown above with reference to FIG. 1. Thus, componentsintroduced in the vehicle system 100, such as engine 110, may be thesame as components in engine system 200. As such, components of enginesystem 200 already introduced in FIG. 1, may not be reintroduced in thedescription of FIG. 2. The engine system 200 is configured forcombusting fuel vapor accumulated in at least one component thereof.Engine system 200 includes a multi-cylinder internal combustion engine,generally depicted at 110, which may propel the automotive vehicle.Engine 110 may be controlled at least partially by control system 90which may include a controller 112 and by input from vehicle operator130 via an input device 132. Control system 90 may also include pedalposition sensor 134 for generating a proportional pedal position signalPP.

Engine 110 includes an intake throttle 165 fluidly coupled to an intakemanifold 144 along an intake passage 142. Air may enter intake passage142 from an air intake system (AIS) including an air cleaner 133 incommunication with the vehicle's environment. Intake throttle 165 mayinclude throttle plate 192. In this particular example, the position ofthrottle plate 192 may be varied by controller 112 via a signal providedto an electric motor or actuator included with intake throttle 165, aconfiguration that is commonly referred to as electronic throttlecontrol (ETC). In this manner, intake throttle 165 may be operated tovary the intake air provided to intake manifold 144 and the plurality ofcylinders therein.

A barometric pressure sensor 196 may be coupled at an inlet of intakepassage 142 for providing a signal regarding barometric pressure (BP). Amanifold air pressure sensor 162 may be coupled to intake manifold 144for providing a signal regarding manifold air pressure (MAP) tocontroller 112. A throttle inlet pressure sensor 161 may be coupledimmediately upstream of intake throttle 165 for providing a signalregarding throttle inlet pressure (TIP) or boost pressure.

Intake manifold 144 is configured to supply intake air or an air-fuelmixture to a plurality of combustion chambers 164 (also termed,cylinders 164) of engine 110. The combustion chambers 164 may bearranged above a lubricant-filled crankcase (not shown), in whichreciprocating pistons of the combustion chambers rotate a crankshaft(not shown). Combustion chambers 164 may be supplied one or more fuelsvia fuel injectors 166. Fuels may include gasoline, alcohol fuel blends,diesel, biodiesel, compressed natural gas, etc. Fuel may be supplied tothe combustion chambers via direct injection (as shown in FIG. 2), portinjection, throttle valve-body injection, or any combination thereof. Itwill be noted that a single fuel injector 166 is depicted in FIG. 2 andthough not shown, each combustion chamber 164 may be coupled with arespective fuel injector 166. In the combustion chambers, combustion maybe initiated via spark ignition and/or compression ignition. Further,exhaust gases from combustion chambers 164 may exit engine 110 via anexhaust manifold (not shown) into an emission control device (not shown)coupled to an exhaust passage (not shown).

Engine system 200 may further include a compressor 114 for providing aboosted intake air charge to intake manifold 144. In the example of aturbocharger compressor, compressor 114 may be mechanically coupled toand driven by an exhaust turbine (not shown) powered by exhaust gasesflowing from the engine. The exhaust turbine may be positioned in theexhaust passage and may be driven by exhaust gases. A wastegate (notshown) may be coupled across the exhaust turbine of the turbocharger.Specifically, the wastegate may be included in a bypass passage coupledbetween an inlet and outlet of the exhaust turbine. By adjusting aposition of the wastegate, an amount of boost provided by the exhaustturbine may be controlled. Alternatively, compressor 114 may be anysuitable intake-air compressor, such as a motor-driven superchargercompressor.

In the configuration illustrated in FIG. 2, compressor 114 draws freshair from air cleaner 133 and flows compressed air through intercooler143. The intercooler may also be termed a charge air cooler. As such,each of compressor 114 and intercooler 143 are positioned upstream ofintake throttle 165. The intercooler 143 cools the compressed air, whichthen flows via intake throttle 165 to intake manifold 144, depending onthe position of throttle plate 192 of intake throttle 165. A compressorinlet pressure sensor 160 is coupled immediately upstream of thecompressor 114 for providing a signal regarding compressor inletpressure (CIP) to controller 112.

One or more bypass passages may be coupled across compressor 114 todivert a portion of intake air compressed by compressor 114 backupstream of the compressor into the compressor inlet. The one or morebypass passages may comprise a bypass passage 186. Additionally oralternatively, the bypass passage 186 may include an aspirator 180,positioned as shown in FIG. 2. Aspirators, may provide low-cost vacuumgeneration when utilized in engine systems, and in some examples may bepassive devices. As such, aspirator 180 may be an ejector, an eductor, aventuri, a jet pump, or similar passive device. Thus, in the descriptionherein, aspirators may alternatively be referred to as ejectors, venturipumps, jet pumps, and eductors.

As depicted in the example of FIG. 2, a first end 145 of passage 186 maybe coupled to intake passage 142 downstream of air cleaner 133 andupstream of compressor 114. A second end 147 of passage 186 may becoupled to intake passage 142, downstream of compressor 114 and upstreamof throttle plate 192. Aspirator 180 may be positioned within the bypasspassage 186 between the first end 145 and the second end 147. In otherwords, the motive outlet of aspirator 180 may be coupled to intakepassage 142 upstream of compressor 114 and upstream of CIP sensor 160via bypass passage 186. Therefore, motive flow of compressed air fromdownstream of the compressor 114 mixed with other fluids that may bedrawn into the aspirator via suction may be streamed into intake passage142 at a location upstream of the compressor and downstream of aircleaner 133 (e.g., at first end 145).

Further, the motive inlet of aspirator 180 may fluidically communicatewith intake passage 142 at a point that is downstream of compressor 114,downstream of intercooler 143, and upstream of intake throttle 165. Inalternative embodiments, the motive inlet of aspirator 180 may befluidically coupled to the intake passage 142 downstream of compressor114 but upstream of intercooler 143.

An amount of air diverted through the bypass passage 186 may depend uponrelative pressures within the engine system. Alternatively, as shown inthe depicted embodiment, a shut-off valve 185 may be included in thebypass passage 186 between second end 147 and the aspirator 180. Asshown, shut-off valve (SOV) 185 is positioned upstream (relative to theflow of compressed air in the compressor bypass passage) of ejector 180.To elaborate, SOV 185 is located in the compressor bypass passage 186 ata position that is upstream of the motive inlet of ejector 180. Noadditional components may be positioned between the ejector 180 and SOV185. Herein, a position of shut-off valve 185 may regulate the amount ofair flowing through the bypass passage 186. By controlling shut-offvalve 185, and varying an amount of air diverted through the bypasspassage, a boost pressure provided downstream of the compressor can beregulated. This enables boost control and also controls compressorsurge. Further, when air is diverted through passage 186, vacuum may begenerated at ejector 180 for a variety of purposes including drawingfuel vapors from a canister via a canister purge valve, applying vacuumto a vacuum consumption device such as a brake booster, or for storagein a vacuum reservoir. SOV 185 may be a binary on/off valve where thevalve may be adjusted between a fully open position and a fully closedposition. In other examples, the SOV 185 may be a continuously variablevalve capable of assuming positions between fully-closed and fully-open.In the fully closed position, gasses do not flow through the SOV 185,and in a fully open position, gasses do flow through the SOV 185, wherean amount of gasses flowing through the SOV 185 increases withincreasing deflection of the SOV 185 away from the closed first positionup to the open second position, for constant pressure differentialsacross the valve. Said another way, an opening formed between an edge ofthe SOV 185 an interior walls of passage 191 may increase withincreasing deflection away from the closed first position towards theopen second position.

Engine system 200 further includes fuel system 40 comprising fuel tank126, fuel vapor canister 122, and other components which will bedescribed further below, and fuel vapor recovery system 140 whichcomprises canister 122, and other components which will be describedfurther below. In the description herein, the fuel vapor canister 122may also be referred to as charcoal canister 122. Thus, the fuel vaporrecovery system 140 may not include the fuel tank 126. Fuel tank 126stores a volatile liquid fuel that may be delivered via fuel supply line131 to fuel injector 166, where fuel injector 166 may regulate a fuelinjection amount to combustion chambers 164 in engine 110. Thus, supplyline 131, may coupled on one end to the fuel tank 126, and on the otherend to fuel injector 166 for delivering liquid fuel thereto.

To avoid emission of fuel vapors from the fuel tank 126 into theatmosphere, the fuel tank 126 may be vented to the atmosphere throughfuel vapor canister 122. Fuel vapor canister may also be referred to asan adsorbent canister, a fuel system canister, a charcoal canister, orsimply, a canister, in the rest of this description. Fuel vapor canister122 may have a significant capacity for storing hydrocarbon-, alcohol-,and/or ester-based fuels in an adsorbed state. The adsorbent canistermay be filled with activated carbon granules and/or another highsurface-area material, for example, to adsorb fuel vapors received fromthe fuel tank. Nevertheless, prolonged adsorption of fuel vapor willeventually reduce the capacity of the adsorbent canister for furtherstorage and may result in bleed emissions. Therefore, the adsorbentcanister may be periodically purged of adsorbed fuel vapors, as furtherdescribed hereinafter. While a single fuel vapor canister 122 is shownin FIG. 2, it will be appreciated that any number of canisters may becoupled in engine system 200.

A vapor blocking valve (VBV) 124 (also termed, fuel tank isolation valve124) may be optionally included in a conduit between fuel tank 126 andfuel vapor canister 122. In some embodiments, VBV 124 may be a solenoidvalve, and operation of VBV 124 may be regulated by adjusting a drivingsignal (or pulse width) of the dedicated solenoid. During normal engineoperation, VBV 124 may be kept closed to limit the amount of diurnalvapors directed to canister 122 from fuel tank 126. During refuelingoperations, and selected purging conditions, VBV 124 may be temporarilyopened to direct fuel vapors from the fuel tank 126 to canister 122. Byopening the fuel tank isolation valve (FTIV) 124 during conditions whenthe fuel tank pressure is higher than a threshold pressure (e.g., abovea mechanical pressure limit of the fuel tank above which the fuel tankand other fuel system components may incur mechanical damage), therefueling vapors may be released into the canister and the fuel tankpressure may be maintained below pressure limits. While the depictedexample shows VBV 124 positioned in a passage between the fuel tank andcanister, in alternate embodiments, the FTIV may be mounted on fuel tank126.

The fuel tank 126 may comprise a baffle 190 which may extend betweenopposite ends of the fuel tank 126, dividing the fuel tank into a firstcompartment 176, and a second compartment 178. Said another way, an edgeof baffle 190 may be in sealing contact with an interior surface of thetank 126, so that the flow of fuel between the first compartment 176 andthe second compartment 178 may be regulated by position of one or morevanes 194. As will be explained in greater detail below with referenceto FIGS. 3-5, the baffle 190 may in some examples comprise one vane 194.However, in other examples, the baffle 190 may comprise more than onevane 194. The vanes 194 are pivotable, and may therefore be adjustedbetween an open first position and a closed second position, where anopening in the baffle providing fluidic communication between the firstcompartment 176 and the second compartment 178 increases with increasingdeflection of the vanes 194 towards the open first position away fromthe closed second position. As such, the flow of fuel between the firstcompartment 176 and second compartment 178 may be regulated by adjustingthe position of the vanes 194.

In some examples, the vanes 194 may be free to rotate on an axisparallel to the baffle 190. The vanes 194 may be held in the closedsecond position by a restoring force, which in the description hereinmay also be referred to as a restraining force, unless acted upon by agreater force which opposes the restoring force. In some examples, therestoring force may be gravity. Thus, the axis of rotation of the vanes194 is not parallel to the force of gravity. In some examples, the axisof rotation of the vanes 194 may be approximately perpendicular to theforce of gravity. In this way, the vanes 194 may be biased to the closedsecond position by their weight. Said another way, the weight of thevanes 194, may provide the restoring force which adjusts the position ofthe vanes 194 to the closed second position. However, during refueling,the pressure force acting on the vanes 194 from the flow of fuel intothe fuel tank 126 may exceed the force of gravity, and therefore maydeflect the vanes 194 away from the closed second position towards theopen first position. Thus, in some examples, each of the vanes 194, mayexert a restraining force to move toward the closed second position.Thus, in examples, where the vanes 194 are free to rotate, therestraining force may be based on the weight of the vanes 194. As such,the retraining force may be less than a threshold pressure force, wherethe threshold pressure force may represent a pressure force in firstcompartment 176, which would cause nozzle 170 to shut off while fuelingfuel tank 126.

In other examples, the restoring force may be provided by a vaneactuator 193. Thus, a vane actuator 193 may be physically coupled to atleast one of the vanes 194, for adjusting the position of the vanes 194.Thus, in the description of vane actuators herein, when a vane actuator193 is described as being physically coupled to a vane 194, the actuator193 is capable of adjusting the position of the vane 194 between theopen first position and the closed second position. In some examples,the engine system 200 may comprise only one actuator 193. The vaneactuator 193 may be physically coupled to one vane 194. However in otherexamples, the vane actuator 193 may be physically coupled to more thanone vane 194, and in some examples may be physically coupled to all ofthe vanes 194.

In other embodiments the engine system 200 may comprise more than onevane actuator 193. In such examples, each vane actuator 193 may bephysically coupled to exactly one vane 194. However, in other examples,each vane actuator 193 may be physically coupled to more than one vane194. In such examples, the vane actuator 193 may be passive and/ormechanical, such as a spring. As such, the position of the vanes 194 maybe passively controlled. Thus, in examples where the actuator 193 is aspring, the spring may provide the restoring force for the vane 194.However, in other examples, the vane actuator 193 may be an activelycontrolled actuator (e.g., motor, electromagnetic actuator, etc.). Insuch examples, the vane actuator 193 may be in electrical communicationwith the controller 112. As such, the controller 112 may send signals tothe vane actuator 193, for adjusting a position of one or more of thevanes 194. An example routine for adjusting the position of the vanes194 based on vehicle operating conditions is described below withreference to FIG. 8.

However, in all examples, the restraining force may maintain the vanes194 in the closed second position except during a refueling event. Thus,the restraining force may maintain the vanes 194 in the closed secondposition while the vehicle 100 is in motion. In further examples, therestraining force may maintain the vanes 194 in the closed secondposition during acceleration of the vehicle 100, such as duringcornering, braking, etc.

It is important to note that in examples where more than one vaneactuator 193 is included in engine system 200, more than one type ofvane actuator 193 may be included. Thus, the position of one of thevanes 194 may be controlled by a spring, while the position of anothervane 194 may be adjusted by an electromagnetic actuator. However, inother examples, only one type of vane actuator 193 may be included.Thus, in some examples, only one or more springs, or only one or moreelectromagnetic actuators, may be physically coupled to the vanes 194for adjusting the positions thereof.

One or more pressure sensors 128 may be coupled to fuel tank 126 forestimating a fuel tank pressure or vacuum level. While the depictedexample shows a pressure sensor coupled to fuel tank 126, in alternateembodiments, pressure sensor 128 may be coupled between the fuel tankand VBV 124. The fuel tank 126 may additionally comprise a fuel levelsensor 173, where outputs from the sensor 173 may be sent to thecontroller 112 for estimating an amount of fuel in the fuel tank 126.Further, outputs from pressure sensor 128 and/or fuel level sensor 173may be used to determine if a refueling event is occurring and/or if arefueling event has occurred. During a refueling event, fuel may beadded to the fuel tank 126 by fuel dispensing nozzle 170. Specifically,fuel dispensing nozzle 170 may be inserted into a filler tube (e.g.,filler tube 310 shown in FIG. 3) for flowing fuel into the fuel tank126. Thus, a refueling event may comprise conditions where the engine110 is off, and fuel is being added to the fuel tank 126. Controller 112may determine if a refueling event is occurring and/or has occurredbased on changes in the fuel level as estimated based on outputs fromthe fuel level sensor 173 and/or pressure changes in the fuel tank 126as estimated based on outputs from the sensor 128. During a refuelingevent, the vanes 194 may be adjusted away from the closed secondposition towards the open first position as described in the examplemethod of FIG. 8. Otherwise the vanes 194 may be adjusted to the openfirst position.

Fuel vapors in fuel tank 126, may be released to the fuel vapor recoverysystem 140, which may comprise charcoal canister 122. Specifically, fuelvapors in fuel tank 126, may be routed to the canister 122 for storage.During a purging operation, fuel vapors stored in canister 122 may bedirected into intake manifold 144 via purge conduit 119. The flow ofvapors along purge conduit 119 may be regulated by canister purge valve164, coupled between the fuel system canister 122 and the engine intakemanifold 144. The quantity and rate of vapors released by the canisterpurge valve may be determined by the duty cycle of an associatedcanister purge valve solenoid (not depicted). As such, the duty cycle ofthe canister purge valve solenoid may be determined by the vehicle'spowertrain control module (PCM), such as controller 112, responsive toengine operating conditions, including, for example, engine speed-loadconditions, an air-fuel ratio, a canister load, etc. By commanding thecanister purge valve to be closed, the controller may seal the fuelvapor recovery system from the engine intake.

An optional canister check valve 152 may be included in purge conduit119 to prevent intake manifold pressure from flowing gases in theopposite direction of the purge flow. However, in other examples, theengine system 200 may not include check valve 152. An estimate of themanifold airflow (MAF) may be obtained from a MAF sensor (not shown)coupled to intake manifold 144, and communicated with controller 112.Alternatively, MAF may be inferred from alternate engine operatingconditions, such as mass air pressure (MAP), as measured by a MAP sensor162 coupled to the intake manifold.

In the configuration shown in FIG. 2, canister purge valve 164 is atwo-port canister-purge valve (CPV) that controls the purging of fuelvapors from the canister into the intake manifold, along each of thepurge conduit 119 and purge bypass conduit 123. Purge conduit 119fluidically couples CPV 164 to intake manifold 144. Purge bypass conduit123 fluidically couples CPV 164 to aspirator 180 and thereon, to intakepassage 142 upstream of compressor 114. Purge bypass conduit 123 isfluidically coupled to an entraining inlet 194 of ejector 180 via secondcheck valve 150. Entraining inlet 194 of ejector 180 may also be termedsuction port 194 of ejector 180. Thus, purge bypass conduit 123 may becoupled on one end to conduit 119 downstream of CPV 164, and on theother end to ejector 180, for flowing purge gasses from CPV 164 tointake passage 142 via aspirator 180.

However in other examples, the purge bypass conduit 123 may be coupleddirectly to the CPV 164. As such, the CPV 164 may be a three-port CPV,where an inlet of the CPV 164 may be fluidically coupled to the canister122, and where a first outlet may be coupled via conduit 119 to theintake manifold 144, and where a second outlet may be coupled to theaspirator 180 via purge bypass conduit 123.

CPV 164, which is depicted schematically in FIG. 2, comprises a solenoidvalve 172 and a flow restriction 174. In the depicted example, flowrestriction 174 may be a sonic choke 174. It will be noted that thesolenoid valve 172 and the sonic choke 174 may be positioned within asingle, common housing of CPV 164. In other words, solenoid valve 172and sonic choke 174 may be located within the same housing of the CPV164. It will also be noted that sonic choke 174 is positioned proximateto solenoid valve 172 within CPV 164. It may be further noted that theCPV may include valves other than solenoid valves and flow restrictionsother than sonic chokes without departing from the scope of the presentdisclosure. Sonic choke 174 may also be termed sonic nozzle 174. Thesonic choke 174 may enable a more accurate metering of flow rate.Further, fuel injection via fuel injectors may be adjusted moreaccurately if purged fuel vapors enter the intake manifold at a steadyflow rate allowing enhanced control of air-fuel ratio, emissions, andengine performance.

Opening or closing of CPV 164 is performed via actuation of solenoidvalve 172 by controller 112. Specifically, a pulse width modulated (PWM)signal may be communicated to the solenoid valve 172 in CPV 164 during acanister purging operation. In one example, the PWM signal may be at afrequency of 10 Hz. In another example, the solenoid valve 172 mayreceive a PWM signal of 20 Hz.

When CPV 164 is open, depending on relative pressure levels within theengine system, purge flow may flow through the CPV 164 and then continueeither into the entraining inlet 194 of ejector 180 via second purgebypass conduit 123, if SOV 185 is not closed, or into the intakemanifold 144 via purge conduit 119. During certain conditions, purgeflow may occur along both purge paths (e.g., purge conduit 119 andsecond purge bypass conduit 123) simultaneously.

A second check valve 150 may be positioned in second purge bypassconduit 123 downstream of CPV 164. Purged vapors may, therefore, flowonly in the direction from CPV 164 towards entraining inlet 194 ofejector 180 and not in the opposite direction. Second check valve 150effectually obstructs fluid flow from aspirator 180 into CPV 164.

Thus, during engine operating conditions, where the SOV 185 is not in aclosed position, gasses from the canister 122 may flow through the CPV164 to one or more of the aspirator 180 via purge bypass conduit 123 andintake manifold 144.

Fuel system 40 may be operated by controller 112 in a plurality of modesby selective adjustment of the various valves and solenoids. Forexample, the fuel system may be operated in a fuel vapor storage modewherein the controller 112 may close CPV 164 and open canister ventvalve 120 and FTIV 124 to direct refueling and diurnal vapors intocanister 122 while preventing fuel vapors from being directed into theintake manifold. In this mode, air stripped of fuel vapors may bestreamed from canister 122 to the atmosphere through canister vent valve120 and vent 117.

As another example, the fuel system may be operated in a refueling mode(e.g., when fuel tank refueling is requested by a vehicle operator),wherein the controller 112 may adjust the valves to depressurize thefuel tank before enabling fuel to be added therein. Therein thecontroller 112 may close canister vent valve (CVV) 120 and open each ofCPV 164 and FTIV 124 to direct excess fuel tank pressure/vacuum into theintake manifold 144 via the canister 122.

As yet another example, the fuel system may be operated in a canisterpurging mode (e.g., when canister is saturated, an emission controldevice has attained light-off temperature, and with the engine running),wherein the controller 112 may open CPV 164, CVV 120, and close FTIV124. By closing the FTIV, the canister can be purged more efficiently.During this mode, vacuum generated either by the intake manifold 144 orby the aspirator 180 may be used to draw fresh air through vent 117 andthrough fuel system canister 122 to purge the stored fuel vapors intointake manifold 144. In this mode, the purged fuel vapors from thecanister, along with air drawn from the atmosphere to enable purging,are combusted in the engine. The purging may be continued until thestored fuel vapors amount in the canister is below a threshold.

In one example, one or more sensors 138 may be coupled to the canister122 to provide an estimate of a canister load (that is, an amount offuel vapors stored in the canister). As an example, sensor 138 may be apressure sensor providing an estimate of canister pressure or canisterload. In another example, the fuel system canister load may be based onthe number and duration of refueling events that have occurred followinga previous canister purging event. While sensor 138 is shown directlycoupled to the canister in FIG. 2, other embodiments may position sensor138 downstream of the canister, or in other locations, without departingfrom the scope of the present disclosure.

It will also be appreciated that vacuum generated by aspirator 180 maybe used for additional purposes other than drawing purge flow, withoutdeparting from the scope of this disclosure. For example, aspiratorgenerated vacuum may be stored in a vacuum reservoir. In anotherexample, vacuum from the aspirator may be used in a brake booster.

Controller 112 may be configured as a microcomputer including amicroprocessor unit, input/output ports, an electronic storage mediumfor executable programs and calibration values, random access memory,keep alive memory, and a data bus. Controller 112 may receive varioussignals from sensors 116 coupled to engine 110 such as fuel level sensor173, pressure sensor 128, BP sensor 196, MAP sensor 162, CIP sensor 160,TIP sensor 161, etc. Furthermore, controller 112 may monitor and adjustthe position of various actuators 118 based on input received from thevarious sensors 116. These actuators may include, for example, vaneactuator 193, intake throttle 165, solenoid valve 172 of CPV 164,canister vent valve 120, FTIV 124, and shut-off valve 185. Storagemedium read-only memory in controller 112 can be programmed withcomputer readable data representing instructions executable by aprocessor for performing the routines described below, as well as othervariants that are anticipated but not specifically listed. Exampleroutines are described herein with reference to FIGS. 3 and 4.

Turning now to FIG. 3, it shows an exterior side perspective view of anembodiment 300 of the fuel tank 126 shown in FIGS. 1-2. In thedescription herein, axis system 330 may be used to describe the relativepositioning of components of the fuel tank 126. The axis system 330 maycomprise a vertical axis 336, a horizontal axis 334, and a lateral axis334. A top wall 326 and bottom wall 324 may define the vertical extentof the fuel tank 126 along the vertical axis 336. Thus, the top wall 326may be referred to as the “top” of the fuel tank 126, where the top ofthe fuel tank 126 may be the top of the fuel tank 126 relative to theground, when fuel tank 126 is coupled to a vehicle system (e.g., vehiclesystem 100 shown in FIG. 1). Similarly the bottom wall 324 may bereferred to as the “bottom” of the fuel tank 126, where the bottom ofthe fuel tank 126, may be the bottom of the fuel tank 126 relative tothe ground, when fuel tank 126 is coupled to a vehicle system.

A front side wall 322, and a back side wall 328 may physically couplebottom wall 324 and top wall 326. Further, two end walls 320, may bepositioned, one at either end, of the fuel tank 126. Thus, the end walls320 may extend along the lateral axis 334. In some examples, as shown inFIG. 3, the end walls 320 may be flat, and walls 322, 324, 326, and 328,may be curved. As such, the fuel tank may be approximately cylindrical.However, it should be appreciated that in other examples, the shape andsize of the fuel tank 126, and the shape, size, and configuration, ofthe walls 320, 322, 324, 326, and 328 may be different than as depictedin FIG. 3. As such, in some examples walls 322, 324, 326, and 328 may beflat. In some examples, the end walls 320, may be circular, oval,triangular, rectangular, or other geometric shape. Further, the endwalls 320 in some examples may not be flat, but may instead by curved.The fuel tank 126 may therefore take on any prismatic shape. Each ofwalls 320, 322, 324, 326, and 328 may be shaped as any geometric shape,or non-geometric shape.

The walls of the fuel tank may be comprised of any suitable materialsuch as plastic, metal, metal alloy, etc. Further, the walls 320, 322,324, 326, and 328 of the fuel tank 126 may be thin, so that they definea hollow interior reservoir of the fuel tank 126 for storing liquidfuel. In some examples, the walls 320, 322, 324, 326, and 328 may be 1mm thick. However, in other examples, the walls 320, 322, 324, 326, and328 may be thicker than 1 mm. In still further examples, the thicknessof the walls 320, 322, 324, 326, and 328 may be less than 1 mm. Thewalls 320, 322, 324, 326, and 328 may be in sealing contact, so thatinterior and exterior portions of the fuel tank 126 are sealed off fromone another and may not be in fluidic communication with one anotherexcept for through one or more of a filler tube 310, supply line 131,and return line 321. Said another way, fuel may only enter and/or exitthe fuel tank 126 through one or more of the filler tube 310, supplyline 131, and return line 321.

As described above with reference to FIGS. 1-2, fuel tank 126 may beconfigured for receiving and storing fuel to be used in combustion of anengine (e.g., engine 110 shown in FIGS. 1-2). Fuel may be dispensed intothe fuel tank 126 from a fuel source, such as nozzle 170. A filler tube310 may be configured for receiving the nozzle 170, and directing fuelfrom the nozzle into the fuel tank 126. Thus, the filler tube 310, maycomprise a first position 312 which extends exterior to the fuel tank126, away from an end wall 320, and a second portion 314 (shown indashed lines) which extends into the interior of the fuel tank 126 froman end wall 320. In this way, the filler tube 310 may extend into theinterior of the fuel tank 126, for delivering fuel thereto. Said anotherway, the filler tube 310 may be partially positioned within the fueltank 126, so that a portion of the filler tube 310 is positioned withinthe fuel tank 126, and another portion of the filler tube 310 ispositioned exterior to the fuel tank 126. Thus, upon insertion of thenozzle 170 into the filler tube 310, fuel may flow from the nozzle 170,into the filler tube 310, and into the interior of the fuel tank 126.Further, the filler tube 310 may be positioned more proximate the bottomof the fuel tank 126 than the top. When coupled in a vehicle systemtherefore, the filler tube 310 may in some examples be coupled to thefuel tank 126 more proximate the bottom of the fuel tank 126 withrespect to the ground than the top of the fuel tank 126.

In some examples, a filler cap 318 may be included in a distal end ofthe filler tube 310. Thus, the filler cap 318 may be positioned on anend of the first portion 312, furthest away from the fuel tank 126. Thecap 318, may be removed before the nozzle 170 may be inserted. Further,the cap 318 may seal the fuel tank 126 when fastened to the end of thefiller tube 310. In further examples, the filler tube 310 may include aposition sensor 316. Outputs from the position sensor 316 may be used toestimate and/or measure a position of the nozzle 170. Thus, a controller(e.g., controller 112 shown in FIGS. 1-2) may determine that a nozzle(e.g., nozzle 170) has been inserted into the filler tube 310 based onoutputs from the position sensor 316.

The fuel tank 126 may also comprise fuel supply line 131 described abovewith reference to FIG. 2, and a return line 321 for receiving fuel notcombusted in the engine. Fuel supply line 131 may in some examples becoupled to a pump (e.g., pump 412 shown in FIG. 4) for providingpressurized fuel to the engine. Thus, fuel supply line 131 may providefluidic communication between the fuel tank 126 and the engine, forsupplying fuel stored in the fuel tank 126 to the engine.

As described above with reference to FIG. 2, an actuator 193 may bephysically coupled to the fuel tank 126. In some examples, the actuator193 may be coupled to the fuel tank 126 via a rotatable rod 304.Specifically, the actuator 193 may be physically coupled to one or morevanes (e.g., vanes 194 shown in FIG. 2), for adjusting the position ofthe vanes. In the example shown in FIG. 3, the actuator 193 may bepositioned external to the fuel tank 126. However, in other examples, asshown in FIGS. 5A-5B, the actuator 193 may be positioned internallywithin the fuel tank 126. As described above with reference to FIG. 2,more than one actuator may be coupled to the fuel tank 126 and/or may bepositioned within the fuel tank 126. Further, the actuator 193, may be apassively, or actively controlled device. In examples where the actuator193 is a passively controlled device, the actuator 193 may be a spring,magnet, etc. In examples where the actuator 193 is actively controlled,the actuator 193 may be a motor, electromagnetic actuator (e.g.,solenoid), etc.

Moving on to FIG. 4, it shows an embodiment 400 of an interior sideperspective view of the fuel tank 126. Thus, FIG. 4 shows the fuel tank126 as depicted in FIG. 3, with the walls 320, 322, 324, 326, and 328illustrated as transparent, exposing the interior of the fuel tank 126.Components that may be contained within the walls of the fuel tank 126,and therefore included interior to the fuel tank 126 are shown withsolid lines. Other components that may be exterior to the fuel tank 126are shown in dashed lines. It is important to note that fuel tank 126 issubstantially hollow, so that the interior of the fuel tank 126, may befilled with gasses and/or liquid.

Baffle 190, described above with reference to FIG. 2 may include one ormore adjustable vanes 194 for regulating the flow of fuel within thefuel tank 126. The baffle 190 may be made of plastic, metal, metalalloy, or any other suitable material. Further, the baffle may extendalong the vertical and lateral axis of the fuel tank 126, so that anedge 414 of the baffle may be in sealing contact with an interiorsurface of walls 322, 324, 326, and 328. Said another way, the baffle190 may extend fully, and may be approximately the same surface area, asa cross-section of the fuel tank 126, taken along cutting plane 420. Assuch, no additional components including air may separate the edge 414of the baffle 190 from the walls 322, 324, 326, and 328. Therefore, thebaffle 190 may divide the fuel tank 126 into two regions, firstcompartment 176, and second compartment 178. Regions 176 and 178 may behollow, and therefore may store liquid fuel. As such, fuel may not flowaround the baffle between the first compartment 176 and secondcompartment 178. Said another way, fuel may only flow between the firstcompartment 176 and second compartment 178 through the baffle 190. Insuch examples, baffle 190, specifically edge 414, may be physicallycoupled to interior surfaces of walls 322, 324, 326, and 328 using anysuitable joining and/or fastening method such as welding, ultrasonicwelding, injection molding, etc. However, in other examples, the baffle190 may not extend between the walls 322, 324, 326, and 328, and assuch, air and/or additional components may separate the baffle 190 fromwalls of the fuel tank 126 such that fuel may flow around the baffle 190between the first compartment 176 and second compartment 178.

As shown in the examples of FIG. 3, the baffle 190 may be planar, andmay have a surface area approximately equal to that of the end walls320. Said another way, the baffle 190, may form a cross section of thefuel tank 126, where the cross-section is taken along the lateral axis332 in the example of FIG. 4. However, in other examples, the baffle 190may not be flat, and may take on other non-planar shapes, such ascurved, wavy, undulating, etc.

Further, in other examples, the baffle 190 may not extend across across-sectional area of the fuel tank 126 taken along cutting plane 420,but instead may extend across a cross-sectional area of the fuel tank126 defined along cutting plane 425. In such examples, the baffle 190may extend along the vertical and horizontal axis of the fuel tank 126,so that the edge 414 of the baffle 190 may be in sealing contact with aninterior surface of walls 320, 324, and 326. As such, the baffle 190 mayextend along the extent of the fuel tank 126 in both the vertical axis336, and horizontal axis 334. In such examples, baffle 190, specificallyedge 414, may be physically coupled directly to interior surfaces ofwalls 320, 324, and 326 using any suitable joining and/or fasteningmethod such as welding, ultrasonic welding, injection molding, etc.

In still further examples, the baffle 190 may not extend across across-sectional area of the fuel tank 126 taken along cutting plane 420,but instead may extend across a cross-sectional area of the fuel tank126 defined along the cutting plane 430. In such examples, the baffle190 may extend along the lateral and horizontal axis, 332 and 334respectively, of the fuel tank 126, so that the edge 414 of the baffle190 may be in sealing contact with an interior surface of walls 320,322, and 328. As such, the baffle 190 may extend along the extent of thefuel tank 126 in both the lateral axis 332, and horizontal axis 334. Insuch examples, baffle 190, specifically edge 414, may be physicallycoupled directly to interior surfaces of walls 320, 322, and 328 usingany suitable joining and/or fastening method such as welding, ultrasonicwelding, injection molding, etc.

Baffle 190 may comprise one or more vanes 194. In some examples, thebaffle 190 may comprise one vane. However, in other examples, the baffle190 may comprise more than one vane. In some examples, the vanes 194 maycomprise approximately four vanes. As will be described in greaterdetail below with reference to FIGS. 5A-5B, the vanes may include aplurality of apertures for providing fluidic communication between thefirst compartment 176 and the second compartment 178. Further, the vanesmay be adjustable between the open first position and closed secondpositions. When in the closed second position, the only fluidiccommunication provided between the first compartment 176 and secondcompartment 178 may be through the apertures, if included, in the vanes194. However, when in the open first position, fluidic communicationbetween the first compartment 176 and second compartment 178 is providedso that fuel may flow therebetween.

The vanes 194 may remain in the closed second position, unless a nozzle(e.g., nozzle 170 shown in FIGS. 1-2), is inserted in the filler tube310. Upon insertion of the nozzle into the filler tube 310, and/orreceiving of the nozzle 170 into the filler tube 310, the vanes 194 maybe enabled to open as described in greater detail below with referenceto FIG. 8. In some examples, where the actuator 193 is a passive devicesuch as a spring, magnet, etc., the vanes 194 may be enabled to open viaa mechanical release of said vanes 194. In other examples, where theactuator 193 is an actively controlled device such as an electromagneticactuator, the vanes 194, may be enabled to open via anelectro-mechanical release of said vanes 194. Further, in examples,where the actuator 193 is an actively controlled device, the actuatormay open the vanes 194 in response to signals received from a controller(e.g., controller 112 shown in FIGS. 1-2), where the controller may sendsignals to the actuator 193 for opening the vanes 194 in response toinput received from various sensor (e.g., fuel level sensor 173). Thus,as described in greater detail below with reference to FIG. 8, inresponse to determining that the nozzle has been inserted into thefiller tube 310, the controller may send signals to the actuator 193 foradjusting the position of the vanes 194 away from the closed secondposition towards the open first position. In still further examples,where the vanes 194 may not be coupled to an actuator, and are free torotate passively, the vanes 194 may be enabled to open by a pressureexerted on said vanes 194 from fuel entering the fuel tank 126 duringrefueling. Thus, the pressure force of fuel acting against the vanes 194during refueling, may in some examples overcome a weight of said vanes194, and therefore move the vanes 194 away from the closed secondposition towards the open first position.

In another embodiment, the position of the vanes 194 may be adjustedbased on an electrical relay from a sensor output. For example, a sensorsuch as sensor 316 shown above in FIG. 3, may send one or more outputsupon insertion of a nozzle (e.g., nozzle 170 shown in FIGS. 1-3). Thesensor output may be amplified by a driver, where the driver may drivean electronic relay to open the vanes 194. Thus, upon detection ofinsertion of the nozzle into filler tube 310, outputs from the sensormay be coupled to a relay or electromechanical device such as actuator193 through a driver, to open the vanes 194.

In some examples, the fuel tank 126 may additionally include one or moreauxiliary baffles 403. As shown in the example of FIG. 4, the auxiliarybaffles 403 may include only one baffle. Thus, in some examples, thefuel tank 126 may comprise exactly two baffles. However, in otherexamples, the auxiliary baffles 403 may comprise more than one baffle.In such examples, the fuel tank 126 may comprise exactly three baffles.In still further examples, the fuel tank 126 may comprise four or morebaffles. The auxiliary baffles 403 may be positioned within the fueltank 126 parallel to the baffle 190. Further, the auxiliary baffles 403may be sized, such that they are approximately the same size as thebaffle 190. In this way, the auxiliary baffles 403 may be in sealingcontact with interior surface of the walls 322, 324, 326, and 328 whenthe baffle 190 is orientated within the fuel tank 126 as shown in FIG.4. Therefore, the auxiliary baffles 403 may divide the fuel tank intomore regions than just the first compartment 176 and second compartment178. The number of regions included in the fuel tank 126 in addition tothe first compartment 176 and second compartment 178, may be the same asthe number of auxiliary baffles 403. Thus, in the example of FIG. 4,where only one auxiliary baffle 403 is included in the fuel tank, oneauxiliary region 407 may be included in the fuel tank 126, on theopposite side of the auxiliary baffle 403 as the second compartment 178.

In some examples, the auxiliary baffles 403 may comprise a plurality ofapertures 405 for providing fluidic communication between regions of thetank adjacent the auxiliary baffle 403. Said another way, fuel may flowthrough the apertures 405, when included, in the one or more auxiliarybaffles 403. However, in other examples, the auxiliary baffle 403 maynot include apertures 405. In examples where two or more auxiliarybaffles 403 are included in the fuel tank 126, any combination or orderof the auxiliary baffles 403 may include apertures 405.

In still further examples, the auxiliary baffles 403 may not be insealing contact with at least four walls of the fuel tank 126, and assuch fuel may flow around the one or more auxiliary baffles 403, betweendifferent regions of the fuel tank 126 divided by the auxiliary baffles403.

Auxiliary baffles 403 may in some examples, additionally include vanes194 in a similar manner as described above for baffle 190. Thus, thevanes 194 may be included one or more auxiliary baffles 403 and theposition of the vanes 194 may be controlled either passively oractively. Specifically a position of the vanes 194 may be adjusted byone or more of a spring, magnet, motor, electromagnetic actuator,solenoid, etc. In still further examples, the vanes 194 may not becoupled to an actuator 193, and the position of the vanes 194 may beadjusted by the weight and orientation of the vanes, and any otherforces acting on the vanes 194 in the fuel tank 126, such as pressureforces. It is important to note that when two or more auxiliary baffles403 are included in the fuel tank 126, not all of the auxiliary baffles403 may comprise vanes 194. Thus, one of the auxiliary baffles 403 mayinclude vanes 194, and another one of the auxiliary baffles 403 may not.

However, in all examples, where the fuel tank 126 includes auxiliarybaffles 403, the auxiliary baffles 403 are not positioned between thebaffle 190 and the filler tube 310. Thus, no additional baffles separatethe baffle 190 comprising the vanes 194, from the filler tube 310. Assuch, fuel entering the fuel tank 126 from filler tube 310, exits fillertube 310, flows into the fuel tank 126, and may flow against the baffle190 and/or vanes 194 of the baffle 190. Further, the fuel may flowagainst baffle 190 before contacting any other baffle. Thus, fuelentering the fuel tank 126 during refueling may not flow past anyauxiliary baffles 403 before passing through the baffle 190.

Fuel tank 126 may additionally comprise a pump 412, for pumping fuel inthe fuel tank 126 to an engine (e.g., engine 110 shown in FIGS. 1-2).Pump 412 may be fluidically coupled to supply line 131, where supplyline 131 may be fluidically coupled on its other end to the engine fortransferring fuel from the fuel tank 126 to the engine. Thus, fuel maybe pumped from the fuel tank 126, through the fuel pump 412, into supplyline 131, to the engine. Additionally fuel level sensor 173 is shown inFIG. 4, for estimating and/or measuring a level of fuel in the fuel tank126.

As explained above with reference to FIG. 3, in some examples, whenincluded, actuator 193 may be exterior to the fuel tank 126. However, inother examples, the actuator may be included within the fuel tank 126,but exterior to the baffle 190. In still further examples, as shownbelow with reference to FIGS. 5A-5B, the actuator may be included withinthe baffle 190.

In this way, a system may comprise: a filler pipe partially positionedin a tank to receive fuel from an external filler nozzle, a first bafflewhich may form a first compartment in said tank into which said fillerpipe may be positioned, where said first baffle may include a pluralityof pivotable vanes, where each vane may exert a restraining force tomove toward a closed position, where said restraining force may be lessthan a minimum force from fuel pressure in said first compartment whichwhen applied against said filler pipe may cause said filler nozzle toshut off while fueling said tank, where said first baffle may furtherinclude a plurality of holes, and a second stationary baffle which maynot include movable vanes which may positioned in said tank to form asecond compartment between said first and second baffles and a thirdcompartment between a side of said second baffle opposite said secondcompartment and a wall of said tank, where said second baffle mayinclude a plurality of holes therein to allow fuel to flow between saidsecond and third compartments. In some examples, the restraining forcemay be based on a weight of said vanes. In other examples, therestraining force may further be based on a return spring coupled tosaid vanes. In yet further examples, the restraining force may be basedon an electro-mechanical device which is activated in response toinsertion of said nozzle into said filler pipe. The restraining forcemay keep said vanes in said closed position while a vehicle driven by aninternal combustion engine is in motion which may include rapidcornering of said vehicle. Further, the filler pipe may be open toward abottom of said tank. In some examples, the system may further comprise afuel system to supply fuel from said tank to an internal combustionengine and a charcoal canister having an inlet coupled to said tank tostore a portion of fuel vapors generated in said tank. Said charcoalcanister may also having an outlet coupled to said internal combustionengine.

Turning now to FIGS. 5A-5B, they show side perspective views of thebaffle 190 included in the fuel tank 126 shown above with reference toFIGS. 1-4. As such, FIGS. 5A and 5B may be discussed together in thedescription herein. FIG. 5A, shows an embodiment 500 where the vanes 194of baffle 190 may be in the open first position, while FIG. 5B shows anembodiment 550 where the vanes 194 may be in the closed second position.The position of the vanes 194 may be adjusted to regulate the flow offuel through the baffle 190. Specifically the position of the vanes 194may be adjusted by an actuator (e.g., actuator 193 shown in FIGS. 2-4).In some examples, the actuator may be a passively controlled actuatorsuch as spring 504. As shown in FIG. 5B, the spring 504 may provide arestoring force to one or more of the vanes 194, so that the vanes 194are biased towards the closed second position. Said another way, thespring 504 may be coupled to one or more of the vanes 194 such that thespring 504 is more compressed with the vanes 194 in the open firstposition than when in the closed second position. Due to the compressionof the spring 504 with increasing deflection of the vanes 194 away fromthe closed first position, the spring 504 provides a restoring force onthe vanes 194, which bias the vanes towards the closed second position.The spring 504 may be compressed upon insertion of a nozzle (e.g.,nozzle 170 shown in FIGS. 1-2) into a filler tube (e.g., filler tube 310shown in FIGS. 3-4). In some examples, the nozzle may provide thecompressive force on the spring, which compresses the spring, andthereby moves the vanes 194 towards the open first position away fromthe closed second position.

In other examples, the actuator may be an actively controlled actuatorsuch as electromagnetic actuator 503. Electromagnetic actuator 503 maybe in electrical communication with a controller (e.g., controller 112shown in FIGS. 1-2). As such the controller may send signals to theelectromagnetic actuator 503 for adjusting a position of the vanes 194.Specifically, upon determining that the nozzle has been inserted intothe filler tube, the controller may send signals to the actuator 503 foradjusting the position of the vanes 194 to a more open position. Saidanother way, the upon determining that the nozzle has been inserted intothe filler tube, the controller may send signals to the actuator 503 foradjusting the position of the vanes 194 towards the open first position,away from the closed second position. Thus, each of the vanes 194 may bephysically coupled to an actuator, such that actuator may adjust aposition of the vanes 194. Specifically, the actuator may be physicallycoupled to one or more vanes 194 for rotating the vane between the openfirst position and the closed second position.

In still further examples, as shown in FIGS. 5A and 5B, one or more ofthe vanes 194 may not be physically coupled to an actuator. In suchexamples, the vanes 194 may still be pivotable, and may be rotated alongaxis X-X.′ Thus, in examples where one or more of the vanes 194 is notcoupled to an actuator, the vanes 194, may be free to move between theopen first position and closed second position based on gravity,pressure, etc. In such examples, the baffle 190 and vanes 194 may bepositioned so that the weight of said vanes 194 biases the vanes 194towards the closed second position. Said another way, the weight of thevanes 194 may exert a restraining force which moves the vanes 194towards the closed second position. The vanes 194 may be adjusted awayfrom the closed second position towards the open first position, when apressure force is exerted on said vanes 194 which exceeds the weight ofsaid vanes 194. As such, the retraining force may be less than athreshold pressure force, where the threshold pressure force may be apressure force inn a compartment on a refueling side of the baffle 190(e.g., first compartment 176 shown in FIGS. 2 and 4), which when appliedagainst a filler pipe (e.g., filler pipe 310 shown in FIGS. 3-4) wouldcause a filler nozzle (e.g., nozzle 170 shown in FIGS. 1-2) to shut offwhile fueling a fuel tank (e.g., fuel tank 126 shown in FIGS. 1-4).

As illustrated in the examples of FIGS. 5A and 5B, the vanes 194, may berectangular, with the longer sides extending along axis X-X.′ However,in other examples, the vanes 194 may comprise other geometric shapes,such as circles, triangles, ellipses, polyhedrons, etc. In someexamples, the vanes 194 may extend along the length of the baffle 190along axis X-X.′ However, in other examples, the vanes 194 may notextend along the length of the baffle 190.

The vanes 194 may be pivotably adjustable. That is, the vanes 194, maybe rotated around an axis X-X.′ In some examples axis X-X′ may beparallel with respect to the ground when baffle 190 is coupled to avehicle system such as vehicle system 100 shown above with reference toFIG. 1. Thus, vanes 194 may be rotated such that in the open firstposition the vanes 194 may be approximately perpendicular to a firstsurface 510 of the baffle 190, and in the closed second position thevanes 194 may be approximately parallel to the first surface 510 of thebaffle 190. As will be described in greater detail below with referenceto FIGS. 6A-6B, each of the vanes 194 may be coupled at one end to arotatable rod 304. The rotatable rod 304 may be coupled to an actuator.Therefore, in some examples, the rotatable rod 304 may be coupled tospring 504. In other examples, the rotatable rod 304 may be coupled toelectromagnetic actuator 503. In still further examples, the rotatablerod 304 may be coupled to both spring 504 and electromagnetic actuator503. Alternatively, rod 304 may not be coupled to spring 504 or actuator503, and may rotate based on its weight, and other natural forces, suchas pressure.

Thus rod 304 may be free to rotate around axis X-X.′ In still furtherexamples more than one rod 304, and therefore more than one of the vanes194 may be coupled to the same actuator. In such examples, more than onerod 304, may be coupled to the electromagnetic actuator 503. In otherexamples, more than one rod 304 may be coupled to the spring 504. Assuch, each actuator such as each spring 504, and/or each electromagneticactuator 503 may be coupled to more than one rod 304, and therefore totwo or more of the vanes 194. As such the actuator 503, and/or spring504, may in some examples adjust the position of two or more vanes 194.

In the example shown in FIG. 5A, the vanes 194 may be adjusted to theopen first position. However, in other examples, only one of the vanes194 may be adjusted to the open first position, while the other vanes194 may remain in the closed second position. Thus, the position of eachof the vanes 194 may be adjusted independently of one another. In suchexamples, each one of the vanes 194 may be coupled to separateactuators. However, in other examples, the position of all of the vanes194 may be adjusted in unison.

As the position of the vanes 194 is adjusted away from the closed secondposition towards the open first position, one or more openings 506 mayform between each of the vanes 194 and the first surface 510 of thebaffle 190. The openings 506 may extend through the baffle 190, from thefirst surface 510 to a second surface 512. Thus, liquid and/or gassesmay flow through the baffle 190 via the opening 504. As such, the sizeof the openings 506, and therefore the amount of liquid and/or gassesflowing through the baffle 190 may increase with increasing deflectionof the vanes 194 towards the open first position away from the closedsecond position.

In the second closed position of the vanes 194, as shown in FIG. 5B, thevanes 194, may be approximately parallel to the first surface 510. Thus,in some examples, the vanes 194 may be approximately flush with thefirst surface 510 when in the closed second position. As such, liquidand/or gasses may not flow through openings 506 when the vanes 194 arein the closed second position. However, one or more of the vanes maycomprise a plurality of apertures 502, which be sized and/or shaped torestrict the flow of liquids and/or fuel through the baffle 190.Although the apertures 502 are shown in FIG. 5B as circular, in otherexamples the apertures 502, may be shaped differently such asrectangular, square, triangular, etc. Further, the relative sizes of theapertures 502 may in some examples be uniform, and in other examples,may be variable. The apertures 502 may be distributed on the vanes 194in a uniform pattern. In other examples the apertures 502 may bedisturbed on the vanes 194 randomly. In still further examples, theapertures 502 may be distributed on the vanes 194 according to amathematical distribution, such as Gaussian.

Thus, in some examples, where the apertures 502 are not included on thevanes 194, flow through the baffle 190, may be restricted so that noliquids and/or gasses may flow through the baffle 190 when all of thevanes 194 are in the closed second position. However, when the apertures502 are included on the vanes 194, liquids and/or gasses may still flow,through the baffle 190, but in a restricted manner. Thus, the apertures502, may be sized, shaped, and orientated on the vanes 194, to act as aflow restriction through the baffle 190, so that flow through the baffle190 may not exceed a threshold. More detailed illustrations of the openfirst position and closed second position of the vanes 194 are shownbelow with reference to FIG. 6A-6B.

It is important to note that the structure and operation of the vanes194 may be included in a similar manner as described above in baffle190, for auxiliary baffles (e.g., auxiliary baffles 403 shown in FIG.4). Thus, vanes 194 may not only be included in baffle 190, but may alsobe included in other fuel tank baffles as well.

Turning now to FIGS. 6A-6B, they show examples positions which the vanes194 may be adjusted to. As such, FIGS. 6A and 6B may be discussedtogether in the description herein. FIG. 6A shows an embodiment 600where the vanes 194 may be in the open first position and FIG. 6B showsan embodiment 650 where the vanes 194 may be in the closed secondposition.

As shown in both FIGS. 6A and 6B, the vanes 194 may be coupled to therotatable rods 304, such that the vanes 194 may be rotated about theaxis of rotation of the rods 304, as described above with reference toFIGS. 5A-5B. In some examples, the vanes 194 may be coupled to the rods304 at a first end 604 of vanes 194. However, in other examples, asshown in the examples of FIGS. 6A-6B, a portion of the vanes 194 mayextend through the rods 304. As such, the vanes 194 may be coupled tothe rods 304 more proximate the first end 604 than a second end 602.

In the open first position as shown in FIG. 6A, the first end 604 of thevanes 194 may be more proximate the interior of baffle 190 than thesecond end 602. Thus, the second end 602 may extend outward from thebaffle 190 in the open first position. In some examples, the vanes 194may be approximately orthogonal to the baffle 190 when in the open firstposition. The openings 506 formed between the vanes 194 and the baffle190 in the open first position, may allow for liquid and/or gasses topass through the baffle 190. When in the open first position therefore,the vanes 194, may not be in sealing contact with one another, or withinterior surface 610 of the baffle 190.

However, in the closed second position, the each of the vanes 194 may bein sealing contact with one or more other vanes 194, and/or interiorsurfaces 610 of the baffle 190. Thus, in the closed second position,openings 506 may not be formed in the baffle, and fluidic communicationbetween opposite sides of the baffle 190 may be restricted.Specifically, the first end 604 a first one of the vanes 194 may be insealing contact with an interior surface 610 of the baffle 190, whilethe second end 602 of that vane may be in sealing contact with the firstend 604 of a second one of the vanes 194. Further, the second end 602 ofa third one of the vanes 194 may be in sealing contact with the interiorsurface 610 of the baffle 190, while the first end 604 of that vane maybe in sealing contact with the second end 602 of a fourth one of thevanes 194. Vanes 194 not in sealing contact with interior surface 610 inthe closed second position, may be in sealing contact with other vanes194 at both their first end 604 and second end 602. Specifically, thefirst end 604 of each of the vanes 194 not in sealing contact withinterior surface 610 in the closed second position, may be in sealingcontact with the second end 602 of an adjacent one of the vanes 194. Anexample method for regulating the flow of liquid and/or gasses throughthe baffle 190 by adjusting the position of the vanes 194 is shown belowin FIG. 8.

Turning now to FIG. 7, it shows an example method 700 for regulating theflow of fuel and/or fuel vapor into and out of a fuel tank (e.g., fueltank 126 shown in FIGS. 1-4). When a vehicle system (e.g., vehiclesystem 100 shown in FIG. 1) comprising an engine (e.g., engine 110 shownin FIGS. 1-2) is not stationary, fuel may slosh around in the fuel tank.Thus, during conditions where the vehicle system is moving, method 700may comprise adjusting pivotable vanes (e.g., vanes 194 shown in FIGS.2, 4-6) of a baffle (e.g., baffle 190 shown in FIGS. 2, 4-6) to a closedsecond position so that the movement of fuel within the fuel tank may bereduced. However, during fueling events, where the fuel tank is beingsupplied with fuel, the vanes may be adjusted to an open first positionas described in greater detail below with reference to FIG. 8.Additionally, fuel vapors in the fuel tank may be routed to a fuel vaporrecovery system (e.g., fuel vapor recovery system 140 shown in FIG. 2),to reduce pressure in the fuel tank during fueling. During enginecombustion, the fuel vapor recovery system may be purged of fuel vapors.Further, fuel from the fuel tank may be supplied to the engine.

Method 700 and all other methods described therein, such as method 800,may be executed by a controller (e.g., 112 shown in FIGS. 1-2). As such,the methods 700, and 800 may be stored in non-transitory memory on thecontroller, and may be executed based on signals received from variousengine sensors (e.g., sensors 128, 173, and 138 shown in FIG. 2).

Method 700 begins at 702 which comprises estimating and/or measuringengine operating conditions. Engine operating conditions may include afuel tank pressure as estimated based on outputs from a fuel tankpressure sensor (e.g., sensor 128 shown in FIG. 2), fuel level asestimated based on outputs from a fuel level sensor (e.g., fuel levelsensor 173 shown in FIG. 2), a canister load as estimated based onoutputs from a canister pressure sensor (e.g., sensor 138 shown in FIG.2), a driver demanded torque as estimated based on input from a vehicleoperator (e.g., vehicle operator 130 shown in FIGS. 1-2) via an inputdevice (e.g., input device 132 shown in FIGS. 1-2), etc.

After estimating engine operating conditions at 702, method 700 may thenproceed to 704, which comprises determining whether or not the engine isoff. Determining if the engine is off may be based on a position of athrottle valve (e.g., throttle plate 192 shown in FIG. 2), fuelinjection amount, MAP sensor (e.g., sensor 162 shown in FIG. 2), avehicle key-off event, the driver demanded torque, etc. Thus, if it isdetermined that fuel is not being injected to the engine, and that theengine is off, then method 700 may continue to 706 which comprisesdetermining if a vehicle stop conditions exists.

A vehicle stop condition may exists if a vehicle system (e.g., vehiclesystem 100 shown in FIG. 1) and in some cases if the engine are notmoving. Determining if the vehicle system is stopped may be based onoutputs from one or more sensors (e.g., a crankshaft sensor, wheelposition sensor, etc.) used in determining the speed of the vehiclesystem. The vehicle may be stopped after a key-off event. However, inother examples the vehicle system may be stopped during idling.

If the vehicle is not moving, and it is determined at 706 that a vehiclestop condition exists, then method 700 may continue to 708 whichcomprises determining if a fueling event is occurring and/or is desired.A fueling event may comprise conditions where fuel is being added to thefuel tank. Thus a fueling event may comprise inserting and/or receivinga nozzle (e.g., nozzle 170 shown in FIG. 1-2) into the fuel tank, andsubsequently dispensing fuel into the fuel tank via a filler tube (e.g.,filler tube 310 shown in FIGS. 3-4) of the fuel tank. In this way, fuelis added to the fuel tank during a fueling event. In the descriptionherein, a fueling event may also be referred to as a refueling event.

Thus, it may determined whether or not a fueling event thus is occurringbased on whether or not the nozzle is inserted in the filler tube, andwhether fuel is being added to the fuel tank. If the nozzle is insertedin the filler tube and/or fuel is being added to the fuel tank, then itmay be determined at 708 that a fueling event is occurring. Determiningwhether or not the nozzle is inserted in the filler tube may be based ona position sensor (e.g., position sensor 316 shown in FIG. 3) disposedwithin the filler tube. In other examples, it may be determined whetheror not the nozzle is inserted based on a position of a fuel tank cap(e.g., cap 318 shown in FIG. 3). It may determined whether or not fuelis being added to the fuel tank based on fuel level in tank. Thus, ifthe fuel level in the tank is increasing, then it may be determined thata fueling event is occurring.

If it is determined at 708 that a fueling event exists, then method 700continues to 710, which comprises adjusting and/or maintaining theposition of the vanes towards an open first position. Thus, in someexamples, method 800 shown in FIG. 8, may be run as a subroutine ofmethod 700 at 710. In other words, method 700 may execute method 800 at710. After adjusting the vanes to the open first position, method 700then returns.

Adjusting of the vanes may in some examples be passively controlled, andin other examples may be actively controlled. As described above withreference to FIGS. 2-5B, one or more of the vanes may be coupled to anactuator (e.g., actuator 193 shown in FIGS. 2-4, spring 504 shown inFIGS. 5A-5B, and actuator 503 shown in FIGS. 5A-5B). However, in otherexamples, the vanes may not be coupled to an actuator. In all examplesthe vanes may be pivotable, and therefore may be adjusted between theopen first position and closed second position. An opening (e.g.,opening 506 shown in FIG. 5A) formed between the vanes and the bafflemay increase with increasing deflection of the vanes away from theclosed second position towards the open first position.

In some examples where, the vanes are passively controlled, and thevanes are not coupled to an actuator, the vanes may be moved towards theopen first position by a pressure force exerted on the vanes by fuel ina compartment (e.g., first compartment 176 shown in FIGS. 1 and 4) ofthe fuel tank, where the compartment may be formed between the baffle,and the filler tube. Said another way, during the fueling event, fuelentering the fuel tank may exert a pressure force on the vanes of thebaffle. The pressure exerted by fuel acting against the vanes during thefueling may be sufficient to overcome a weight of the vanes, where theweight of the vanes may exert a closing force on said vanes, biasing thevanes towards the closed second position.

However in other examples, where the vanes may be passively controlledby the spring and/or other passive device (e.g., magnet), the vanes maybe adjusted towards the open first position by a mechanical release ofthe vanes. Thus, upon insertion of the nozzle into the fuel tank, thevanes may be adjusted to the open first position by a mechanical releaseof the vanes. In some examples, the nozzle may provide a compressiveforce, which enables the mechanical release of the vanes. Thus, in someexamples, where the vanes are coupled to one or more springs, the nozzlemay provide a compressive force to the spring.

In still further examples, where the vanes are actively controlled, suchas by an electromagnetic actuator (e.g., electromagnetic actuator 503shown in FIG. 5A), the vanes may be adjusted to the open first positionby the actuator. Specifically, the actuator may adjust the position ofthe vanes based on signals received from the controller, where thecontroller may send signals to the actuator for adjusting the vanes tothe open first position in response to the nozzle being inserted intothe filler tube.

Returning to 708, if it is determined that the fuel tank is not beingfueled, then method 700 may proceed to 712, which comprises not purgingthe fuel vapor recovery system. Alternatively, method 700 may proceed to712 if it is determined at 706, that the vehicle is moving. Method 700may therefore proceed to 712 from either 706 if the vehicle is notstopped, or from 708 if the fuel tank is not being fueled. Thus, in someexamples, the method 700 at 712 may comprise not purging a charcoalcanister (e.g., canister 122 shown in FIG. 2), where the canister may beincluded in the fuel vapor recovery system. Specifically, the method 700at 712 may comprise closing a CPV (e.g., CPV 164 shown in FIG. 2), and aCVV (e.g., CVV 120 shown in FIG. 2). Closing of the CPV and CVV maycomprise adjusting the position to a fully closed position where gassesand/or fluids do not flow through the valves.

Method 700 may then continue from 712 to 726 which comprises determiningif the fuel tank pressure is greater than a threshold. As describedabove the fuel tank pressure may be estimated based on outputs from thefuel tank pressure sensor. If the fuel tank pressure is greater than thethreshold at 726, method 700 may continue to 728 which comprises routingfuel vapors from the fuel tank to the fuel vapor recovery system.Specifically, the method 700 at 728 may comprise routing fuel vaporsfrom the fuel tank to the canister. In some examples, routing of thefuel vapors to the fuel vapor recovery system and/or the canister maycomprise opening an FTIV (FTIV 124 shown in FIG. 2). Opening of the FTIVmay comprise adjusting the position of the FTIV towards a more openposition, where an opening formed by the FTIV may increase, and therebyan amount of fuel vapors flowing through the FTIV to the canister mayincrease. In some examples, the method 700 at 728 may additionally oralternatively comprise opening the CVV. Opening of the CVV may compriseadjusting the position of the CVV towards a more open position, so thatan opening formed between an edge of the CVV and vent (e.g., vent 117)in which the CVV is positioned may increase, and therefore an amount ofgasses flowing through the CVV may increase.

However, if it is determined at 726 that the fuel tank pressure is notgreater than the threshold, method 700 may not route fuel vapors fromthe fuel tank to the canister, and may proceed directly to 730 from 726.As such, if the fuel tank pressure is not greater than the threshold at726, method 700 may comprise closing the FTIV.

Method 700 may then proceed from 728 or from 726 if it determined at 726that the fuel tank pressure is not greater than the threshold, to 730,which comprises adjusting and/or maintaining the vanes in the closedsecond position. In the closed second position, gasses and/or liquidsmay flow only through apertures (e.g., apertures 502 shown in FIGS.5A-5B) in the vanes, when flowing through the baffle. Thus, when thevanes are in the closed second position, gasses and/or liquids may notflow through the baffle, except through the apertures. The vanes may beadjusted in a similar manner as described above at 710.

In some examples where, the vanes are passively controlled, and thevanes are not coupled to an actuator, the vanes may be moved towards theclosed second position by a restraining force exerted on the vanes by aweight of the vanes. Said another way, gravity may exert the restoringforce on the vanes, biasing the vanes towards the closed secondposition.

However in other examples, where the vanes may be passively controlledby the spring and/or other passive device (e.g., magnet), the vanes maybe adjusted towards the closed second position by the restraining forceof the passive device. In examples where the passive device is a spring,the spring may be more compressed in the open first position than in theclosed second position. Thus, potential energy stored in the spring inthe open first position may provide the restoring force, biasing thevanes towards the second closed position.

In still further examples, where the vanes are actively controlled, suchas by an electromagnetic actuator (e.g., electromagnetic actuator 503shown in FIG. 5A), the vanes may be adjusted to the closed secondposition by the actuator. Specifically, the actuator may adjust theposition of the vanes based on signals received from the controller,where the controller may send signals to the actuator for adjusting thevanes to the closed second position when the fuel tank is not beingfueled. After adjusting the vanes to the closed second position, method700 may then return.

Returning to 704, if it is determined that the engine is on, method 700may continue to 714 which comprises supplying fuel to the engine fromthe fuel tank based on the driver demanded torque. Fuel may be suppliedto the engine from the fuel tank via a supply line (e.g., supply line131 shown in FIGS. 2-4). More specifically, fuel may be pumped from thefuel tank to the engine from a fuel pump (e.g., pump 412 shown in FIG.4) positioned in the fuel tank. The amount of fuel supplied to theengine may be based on the driver demanded torque and/or a position ofthe throttle valve, and a known air/fuel ratio, manifold air pressure,boost level, etc.

Next, the method 700 may continue from 714 to 716, which comprisesdetermining if the canister loading is greater than a threshold. Thecanister loading level may be estimated based on a pressure in thecanister, where the pressure in the canister may be estimated based onoutputs of canister pressure sensor. If the canister load level is lessthan the threshold at 716, method 700 may not purge the canister, andmay continue to 726. Further, not purging the canister may compriseclosing the CPV. However, if the canister load is greater than thethreshold at 716, method 700 may continue to 718 which comprises purgingthe fuel vapor recovery system. Purging the fuel vapor recovery systemmay comprise purging the canister.

As such, the method 700 at 718 may include one or more of opening theCPV at 720, opening the CVV at 722, and closing the FTIV at 724. Closingof the FTIV may comprise adjusting the position of the FTIV towards amore closed position, where an opening formed by the FTIV may decrease,and thereby an amount of fuel vapors flowing through the FTIV to thecanister may decrease. In some examples, the FTIV may be adjusted to afully closed position so that gasses do not flow through the FTIV. Insome examples, the method 700 at 728 may additionally or alternativelycomprise opening the CVV. Opening of the CPV may comprise adjusting theposition of the CPV towards a more open position, so that an openingformed between an edge of the CPV and a purge conduit (e.g., conduit 119shown in FIG. 2) in which the CPV is positioned may increase, andtherefore an amount of gasses flowing through the CPV may increase.

Thus, in some examples, purging of the fuel vapor recovery system maycomprise flowing fuel vapor gasses from the canister to an intakemanifold (e.g., intake manifold 144 shown in FIG. 2) of the engine viathe purge conduit. Additionally or alternatively, purging of the fuelvapor recovery system may comprise flowing fuel vapor gasses from thecanister to an aspirator (e.g., aspirator 180 shown in FIG. 2) coupledacross a compressor bypass conduit (e.g., bypass passage 186 shown inFIG. 2), via a purge bypass conduit (e.g., purge bypass conduit 123shown in FIG. 2). After purging the fuel vapor recovery system at 718,method 700 may then continue to 726, and may proceed to one or more of728 and 730 in the manner described above, before returning.

In this way, the method 700 may comprise adjusting the vanes dependingon whether or not the fuel tank is being fueled. During fueling, thevanes may be adjusted to an open first position. However, when the fueltank is not being fueled, the vanes may be adjusted to the closed secondposition. If the pressure in the fuel tank exceeds a threshold duringvehicle operation, the fuel tank may release a portion of the fuelvapors to the fuel vapor recovery system. Additionally, the fuel vaporrecovery system may periodically be purged to one or more of the intakemanifold and/or aspirator depending on vacuum levels at each. Thus, whenthe canister loading exceeds a threshold, the engine is on, and vacuumin the intake manifold is sufficient to draw stored fuel vapors from thecanister, the CPV may be opened to allow fuel vapors stored in thecanister to be purged to the intake manifold.

Moving on to FIG. 8, it shows an example method 800, for regulating theflow liquids and/or gasses in a fuel tank (e.g., fuel tank 126 shown inFIGS. 1-4). Specifically, method 800 is an example method which may beexecuted for regulating the flow of fuel and/or fuel vapors in the fueltank, during a fueling event by adjusting a position of one or morevanes (e.g., vanes 194 shown in FIG. 2 and FIGS. 4-6B) included in abaffle (e.g., baffle 190 shown in FIG. 2 and FIGS. 4-6B). As such,method 800 may executed as a subroutine of method 700 described abovewith reference to FIG. 7 at 710. Method 800 may include maintaining thevanes in a closed second position so that fuel may only flow through thebaffle via apertures (e.g., apertures 502 shown in FIGS. 5A-5B)positioned within one or more of the vanes, while one or more of anengine (e.g., engine 110 shown in FIGS. 1-2) is running, a vehiclesystem (e.g., vehicle system 100 shown in FIG. 1) is moving, etc.However, during a fueling event, where the engine is off, the vehiclesystem is not moving, and fuel is being added to the fuel tank, thevanes may be adjusted towards an open first position, away from theclosed second position, to increase an opening in the baffle, andtherefore increase an amount of fuel flowing through the baffle.

Method 800 may begin at 802 by estimating and/or measuring engineoperating conditions. Engine operating conditions may include a fueltank pressure as estimated based on outputs from a fuel tank pressuresensor (e.g., sensor 128 shown in FIG. 2), fuel level as estimated basedon outputs from a fuel level sensor (e.g., fuel level sensor 173 shownin FIG. 2), a canister load as estimated based on outputs from acanister pressure sensor (e.g., sensor 138 shown in FIG. 2), a driverdemanded torque as estimated based on input from a vehicle operator(e.g., vehicle operator 130 shown in FIGS. 1-2) via an input device(e.g., input device 132 shown in FIGS. 1-2), etc.

After estimating and/or measuring engine operating conditions, method800 may proceed to 804 which comprises determining if a fueling event isoccurring and/or is desired in a similar manner as described above at708 of method 700 in FIG. 7. If a fueling event is not occurring and/oris not desired at 804, method 800 may proceed to 805 which comprisesadjusting the vanes to a closed second position in the manner describedat 730 of method 700 in FIG. 7. Method 800 then returns.

However, if it is determined that a fueling event is desired at 804,then method 800 may continue to 806 which comprise inserting and/orreceiving a nozzle (e.g., nozzle 170 shown in FIGS. 1-2) into a fillertube (e.g., filler tube 310 shown in FIGS. 3-4). After inserting thenozzle into the filler tube, and/or receiving of the nozzle at 806,method 800 may proceed to 808 which comprises checking to see if thenozzle was inserted and/or received into the filler tube. If the nozzleis not inserted into the filler tube, then method 800 may proceed to 805and adjust the vanes to the closed second position. However, if thenozzle is inserted into the filler tube, then method 800 may proceed to810 which comprises adjusting the vanes to an open first position in themanner described above at 710 of method 700 in FIG. 7.

Upon adjusting of the vanes to the open first position at 810, method800 may then continue to 812 which comprises routing fuel vapors fromthe fuel tank to the fuel vapor recovery system (e.g., fuel vaporrecovery system 140 shown in FIG. 2). The method at 812 may thereforecomprise routing fuel vapors from the fuel tank to canister (e.g.,canister 122 shown in FIG. 2). Specifically, the method 800 at 812 maycomprise opening an FTIV (e.g., FTIV 124 shown in FIG. 2) and flowingfuel vapors from the fuel tank to the canister. Further, the method at810, may additionally or alternatively comprise opening a CPV (e.g., CPV164 shown in FIG. 2) in the manner described at 720 of method 700 inFIG. 7. Additionally or alternatively, the method 800 at 810 maycomprise closing a CVV (e.g., CVV 120 shown in FIG. 2).

The method 800 may then proceed to 814 which comprises fueling the fueltank. Thus, after inserting the nozzle into the filler tube, the method800 may comprise fueling the fuel tank. Fueling of the fuel tank maycomprise flowing fuel through the filler tube into a first compartment(e.g., first compartments 176 shown in FIGS. 2, 4) of the fuel tank at816. The first compartment may be a portion of the fuel tank definedbetween where the filler tube enters the fuel tank, and the bafflecomprising the pivotable vanes. Additionally or alternatively, fuelingthe fuel tank may comprise flowing fuel against vanes in the baffle at820, after flowing fuel into the fuel tank through the filler tube.

Method 800 may then continue to 822 which comprises maintaining thevanes in the open first position during the fueling. Thus, during thefueling, in response to the nozzle being inserted into the filler tube,the vanes may be maintained in the open first position. In someexamples, the vanes may be maintained in the open first position by aforce of the fuel in the fuel tank exerted on the vanes which may begreater than a weight of the vanes. In other examples, the vanes may bemaintained in the open first position by a mechanical release of thevanes. In still further examples, the vanes may be maintained in theopen first position by an electro-mechanical release of the vanes.

In some examples, method 800 may additionally comprise flowing fuelthough openings (e.g., openings 506 shown in FIG. 5A) formed between thevanes and the baffle at 824. Thus, as described above with reference toFIG. 5A, the openings may provide fluidic communication through thebaffle, when the vanes are adjusted to the open first position. As such,during fueling, the method 800 at 824 may comprise flowing fuel throughthe filler tube into the fuel tank, against the vanes of the baffle, andupon adjusting of the vanes to the open first position, the method 800may additionally comprise flowing fuel through the openings formedbetween the vanes and the baffle. Further fuel may flow through theopenings, through the baffle, and into a second compartment (e.g.,second compartment 178 shown in FIGS. 1, 4) formed on the opposite sideof the baffle in the fuel tank.

Next, method 800 may continue to 826 which comprises determining if therefueling of the fuel tank is complete, which may be based on one ormore of the pressure in the fuel tank, an amount of fuel in the fueltank as estimated based on outputs from the fuel level sensor, etc.Thus, fueling may be complete if the pressure in the fuel tank reaches athreshold, and/or if the fuel level in the fuel tank reaches a thresholdfuel level. If fueling of the fuel tank is not complete, method 800 mayreturn to 814 and continue to fuel the fuel tank. If fueling of the fueltank is complete, then method 800 may continue to 828 which comprisesstopping fueling of the fuel tank, and not flowing fuel to the fueltank. Thus, at 828, fuel may no longer flow into the filler tube. Method800 then returns.

In one representation, a method may comprise fueling a fuel tank byreceiving a nozzle into a filler tube which extends into a fuel tank tofuel the fuel tank, and directing fuel through said tube against vanesin a baffle which forms a compartment within said tank, and during saidfueling, the method may comprise enabling said vanes to open so thatpressure within said compartment remains below a level which mayotherwise cause shut off said nozzle. In some examples, enabling saidvanes to open may comprise a mechanical release of said vanes inresponse to insertion of said nozzle. Enabling said vanes to open maycomprise an electro-mechanical release of said vanes by a relay inresponse to insertion of said nozzle. In other examples, enabling saidvanes to open may comprise pressure exerted by said fuel acting againstsaid vanes during said fueling which is sufficient to overcome a weightof said vanes exerting a closing force on said vanes. The vanes may bepositioned in a closed position when said fueling is not occurring.Additionally or alternatively, the method may comprise supplying saidfuel from said tank to an engine driving a motor vehicle. The vanes mayremain closed while said motor vehicle is in motion.

In another representation, a method may comprise fueling a fuel tank byreceiving a nozzle into a filler tube which extends into said tank anddirecting fuel through said tube against vanes in a baffle which forms acompartment within said tank, said vanes including a plurality of holesto allow a portion of said fuel to flow therethrough, during saidfueling, enabling said vanes to open so that pressure within saidcompartment remains below a level which would otherwise cause shut offsaid nozzle, routing fuel vapors from said tank into a fuel vaporrecovery system, supplying said fuel from said tank to an internalcombustion engine, and periodically purging at least a portion of saidfuel vapors from said tank and said fuel vapor recovery system into saidengine. The internal combustion may drive a motor vehicle and saidbaffle may reduce sloshing of said fuel and generation of said fuelvapors while said motor vehicle is being driven. Additionally oralternatively, an electric motor may be utilized for periodicallydriving said motor vehicle. In some examples, enabling said vanes toopen may comprise a mechanical release of said vanes in response toinsertion of said nozzle. In other examples, enabling said vanes to openmay comprise an electro-mechanical release of said vanes by a relay inresponse to insertion of said nozzle. In yet further examples, enablingsaid vanes to open may comprise pressure exerted by said fuel actingagainst said vanes during said fueling which may be sufficient toovercome a weight of said vanes exerting a closing force on said vanes

In this way, a method may comprise during fueling of a fuel tank,inserting a nozzle into a filler tube of the fuel tank, and flowing fuelinto the filler tube in route to the fuel tank. Further, the method maycomprise flowing the fuel into the fuel tank, against pivotable vanesincluded in a baffle of the fuel tank, the baffle defining a compartmentwithin the fuel tank. The vanes may be adjusted between an open firstposition and a closed second position. In the closed second position,fuel may only flow through the baffle through apertures in the vanes.Thus, fuel may not flow through the baffle, when the vanes are in theclosed second position, except through the apertures. However, as thevanes are adjusted towards the open first position, an opening may formbetween the vanes and the baffle, where the size of the opening mayincrease with increasing deflection of the vanes away from the closedsecond position towards the open first position.

Thus, the method may comprise adjusting the vanes to the open firstposition during fueling, so that fuel flowing into the compartment ofthe fuel tank may flow against the vanes, through the openings formed bythe vanes and the baffle, through the baffle, and into a secondcompartment of the fuel tank. In this way, fuel flow through the baffleduring fueling may be increased. Further, opening the vanes duringfueling may reduce pressure in the first compartment. A first technicaleffect of increasing the fuel capacity of the fuel tank is achieved byreducing pressure in the fuel tank during fueling by adjusting the vanesto the open first position. By reducing the pressure in the tank, fuellevels in the tank may reach higher levels before fuel from the nozzleis shut off. A second technical effect of reducing loading of a fuelvapor canister is achieved by reducing vapor pressure in the tank byadjusting the vanes to the open first position.

However, when the fuel tank is not being refueled, the vanes may beadjusted to the closed second position, so that fuel flow through thebaffle may be limited by the apertures. In this way, after fueling ofthe fuel tank, and during acceleration which may cause movement of thefuel within the fuel tank, the sloshing of fuel in the fuel tank may bereduced. Thus, a technical effect of reducing noise generated in thefuel tank from fuel impacting walls of the fuel tank is achieved byadjusting the vanes to a closed second position when the fuel tank isnot being fueled. In this way, by including pivotable vanes in one ormore baffles of a fuel tank, sound generated from the fuel tank may bereduced, while the storage capacity of the fuel tank may be increased,and loading of a charcoal canister may be reduced. Thus, premature fuelshutoffs at fuel tank refueling may be reduced.

Note that the example control and estimation routines included hereincan be used with various engine and/or vehicle system configurations.The control methods and routines disclosed herein may be stored asexecutable instructions in non-transitory memory and may be carried outby the control system including the controller in combination with thevarious sensors, actuators, and other engine hardware. The specificroutines described herein may represent one or more of any number ofprocessing strategies such as event-driven, interrupt-driven,multi-tasking, multi-threading, and the like. As such, various actions,operations, and/or functions illustrated may be performed in thesequence illustrated, in parallel, or in some cases omitted. Likewise,the order of processing is not necessarily required to achieve thefeatures and advantages of the example embodiments described herein, butis provided for ease of illustration and description. One or more of theillustrated actions, operations and/or functions may be repeatedlyperformed depending on the particular strategy being used. Further, thedescribed actions, operations and/or functions may graphically representcode to be programmed into non-transitory memory of the computerreadable storage medium in the engine control system, where thedescribed actions are carried out by executing the instructions in asystem including the various engine hardware components in combinationwith the electronic controller.

It will be appreciated that the configurations and routines disclosedherein are exemplary in nature, and that these specific embodiments arenot to be considered in a limiting sense, because numerous variationsare possible. For example, the above technology can be applied to V-6,1-4, 1-6, V-12, opposed 4, and other engine types. The subject matter ofthe present disclosure includes all novel and non-obvious combinationsand sub-combinations of the various systems and configurations, andother features, functions, and/or properties disclosed herein.

The following claims particularly point out certain combinations andsub-combinations regarded as novel and non-obvious. These claims mayrefer to “an” element or “a first” element or the equivalent thereof.Such claims should be understood to include incorporation of one or moresuch elements, neither requiring nor excluding two or more suchelements. Other combinations and sub-combinations of the disclosedfeatures, functions, elements, and/or properties may be claimed throughamendment of the present claims or through presentation of new claims inthis or a related application. Such claims, whether broader, narrower,equal, or different in scope to the original claims, also are regardedas included within the subject matter of the present disclosure.

1-13. (canceled)
 14. A system, comprising: a filler pipe partiallypositioned in a tank to receive fuel from an external filler nozzle; afirst baffle forming a first compartment in said tank into which saidfiller pipe is positioned, said first baffle including a plurality ofpivotable vanes each exerting a restraining force to move toward aclosed position, said restraining force being less than a minimum forcefrom fuel pressure in said first compartment which when applied againstsaid filler pipe would cause said filler nozzle to shut off whilefueling said tank, said first baffle further including a plurality ofholes; and a second stationary baffle without movable vanes which ispositioned in said tank to form a second compartment between said firstand second baffles and a third compartment between a side of said secondbaffle opposite said second compartment and a wall of said tank, saidsecond baffle including a plurality of holes therein to allow fuel toflow between said second and third compartments.
 15. The system recitedin claim 14, wherein said restraining force is based on a weight of saidvanes.
 16. The system recited in claim 14, wherein said restrainingforce is further based on a return spring coupled to said vanes.
 17. Thesystem recited in claim 14, wherein said restraining force is based onan electro-mechanical device which is activated in response to insertionof said nozzle into said filler pipe.
 18. The system recited in claim14, wherein said restraining force keeps said vanes in said closedposition while a vehicle driven by an internal combustion engine is inmotion including rapid cornering of said vehicle.
 19. The system recitedin claim 14, wherein said filler pipe is open toward a bottom of saidtank.
 20. The system recited in claim 14, further comprising a fuelsystem to supply fuel from said tank to an internal combustion engineand a charcoal canister having an inlet coupled to said tank to store aportion of fuel vapors generated in said tank and also having an outletcoupled to said internal combustion engine.
 21. A method, comprising:positioning a baffle including an adjustable vane between a firstcompartment and a second compartment of a fuel tank, fluidly separatingsaid first compartment and said second compartment by closing saidadjustable vane, fluidly coupling said first compartment and said secondcompartment by opening said adjustable vane, and opening said adjustablevane in response to a pressure in said first compartment increasingabove a threshold pressure.
 22. The method of claim 21, furthercomprising during refueling of said fuel tank, receiving a nozzle into afiller tube which extends into said first compartment, directing fuelthrough said filler tube to said first compartment while said pressurein said first compartment is less than the threshold pressure, andstopping fuel flow through said nozzle in response to said pressure insaid first compartment increasing above said threshold pressure.
 23. Themethod of claim 21, wherein positioning said baffle includes positioningonly said baffle without positioning another baffle in said firstcompartment.
 24. The method of claim 21, further comprising sealinglycontacting a perimeter edge of said baffle with an interior surface ofsaid fuel tank, wherein fluid flows from said first compartment to saidsecond compartment only when said adjustable vane is opened.
 25. Themethod of claim 21, further comprising opening said adjustable vane inresponse to refueling said fuel tank.
 26. The method of claim 21,wherein fluidly separating said first compartment and said secondcompartment by closing said adjustable vane includes sealinglycontacting said adjustable vane with an interior surface of said baffle.27. The method of claim 21, wherein fluidly separating said firstcompartment and said second compartment by closing said adjustable vaneincludes forming no openings in said baffle.
 28. The method of claim 21,further comprising closing said adjustable vane in response to notrefueling said fuel tank.
 29. The method of claim 21, further comprisingdelivering fuel from said second compartment to an engine withoutdelivering fuel from said first compartment to said engine while saidadjustable vane is closed.